Putting is an object of great concern among golfers as the game of golf is designed such that to complete a round of golf (18 holes) with a regulation score of par, approximately one half of all strokes in the par round are allocated to putting. Putting is a unique element of the game of golf, requiring a totally different stroke and set of skills as compared to the swinging motion required for driving and hitting the golf ball with other golf clubs such as woods and irons. The putt is also one of the most troublesome elements of golf as the ideal putting stroke requires very precise and repeatable or grooved stroke dynamics to enable the golfer to impart an exact amount of force to the golf ball and direct the ball along a desired line the required distance to the hole.
Two important problems face golfers in achieving the ideal putting stroke. First of all, it is important that the golf ball be struck at or near its horizontal centerline so as to impart optimum roll dynamics to the ball as will be hereinafter further explained. Secondly, it is important to contact the golf ball at the center of percussion location on the club face because, as explained hereinafter, contacting the golf ball with the face of the putter away from or out-of-alignment with the center of percussion thereof will impart a torsional or twisting motion to the club face which will result in poor performance. Poor putting performance translates into a putt which is too long or too short, a putt which is off line, or a putt in which the golf ball skips or bounces to some degree instead of having a smooth roll. These two factors contribute the most to poor putting and not only negatively affect the outcome of the putt, but, more importantly, they affect the golfer's putting consistency as well as the golfer's confidence level. This negative affect on the outcome of the putt is compounded by the very fact that the size and weight of the golf ball is such that it will react to any obstruction within its path such as the grain of the grass, bare spots, spike marks, wind, moisture and any sand or dirt particles which may lie within its path. Striking the ball incorrectly with the putter face away from the center of percussion of the putter can also give the putt a dead or otherwise poorly hit feeling. As a result, golf putters come in all shapes, sizes, styles and weights in an effort to alleviate these problems.
Numerous apparatus and methods have been directed to balancing golf clubs to improve the feel and performance of the golf swing. For instance, Benoit U.S. Pat. Nos. 4,674,324 and 4,674,746 disclose a golf club swing weighting method wherein a set of golf clubs consisting of a variety of different woods and irons can be balanced such that all clubs have the same static moment associated with the optimum moment of inertia preferred by the golfer. The Benoit method includes varying the radius of gyration of each golf club so as to enable the center of percussion of each such club to remain in the club head while the resulting static moment associated with an individual golfer's optimum moment of inertia is then held constant and matched to all clubs in the set. The Benoit method is limited, however, as the controlling parameter, namely, the resulting static moment, is still a static parameter. The Benoit method is further limited as it is not specifically adaptable for use in balancing putters.
Other known prior art balancing methods disclose adding weight to a golf club to influence performance and feel, namely, adding weight to the grip end of the club. For instance, Mitchell U.S. Pat. No. 4,461,479 discloses a golf club having a weighted handle which moves the balance point of the golf club closer to the grip end for improving accuracy and control when swinging the club Reisner U.S. Pat. No. 4,988,102 discloses a weighted golf grip for balancing a golf club wherein a weight assembly is added to the grip of a golf club at the furthest point opposite the club head behind the golfer's hands. This is done to move the fulcrum point or center of gravity of the club closer to the grip end to provide greater control over the club during the swinging motion. Contrasted to the present method for dynamically balancing a golf putter using radius of gyration as the controlling parameter, the known prior art methods make no effort to align the center of percussion location with the actual golf ball contact point on the club face nor do such prior art methods specifically address the dynamic balancing of golf putters. Also, importantly, all such known prior art methods are tied to static parameters which alone do not provide accurate means for replicating dynamic feel and performance.
Still other prior art balancing methods disclose means for adding weight to the grip end of a golf club to compensate for the tendency of the club head to pull the golf club down and away from the desired swing path. For instance, Stuff et al U.S. Pat. No. 4,203,598 discloses a balancing method for a golf club based on the Parameters of total club weight, center of gravity length and true swing weight of the club, which true swing weight is to be matched to the swing weight of other clubs in a particular set, and wherein a relatively small component weight W.sub.x is also added at the grip end of the club at a radially displaced location from the center of the club shaft to compensate for forces which tend to move the shaft of the golf club downwardly and out of the swing plane. This method is again tied to static parameters and likewise avoids and/or circumvents the dynamic characteristics of a golf club. The Stuff et al method does not incorporate the important dynamic Parameter of radius of gyration into its balancing methodology, nor does it disclose a method for specifically balancing golf putters. Other prior art balancing methods are also discussed in Applicant's U.S. Pat. No. 5,094,101, which patent addresses a method for dynamically balancing golf clubs other than putters.
Contrasted to the relatively limited known weighting and balancing methods and apparatus discussed above, the present invention relates to a method specifically directed to dynamically balancing a golf putter so that it has both a desired radius of gyration and a center of percussion location that will provide optimal performance, feel and putting capability to a particular user of such putter. The present method allows a golfer to obtain maximum power and a truer directional roll by modifying the putter to fit the golfer's natural putting stroke instead of changing the golfer's putting stroke to conform to the particular shape, style, weight and characteristics of the putter being used.